.xaml
<ComboBox x:Name="myCombobox" Width="300" Height="30">
<ComboBox.ItemTemplate>
<DataTemplate>
<StackPanel Width="260" Orientation="Horizontal">
<TextBlock Text="{Binding ID}"/>
<TextBlock Text="."/>
<TextBlock Text="{Binding Name}"/>
<TextBlock Text="("/>
<TextBlock Text="{Binding Count}" Foreground="Red"/>
<TextBlock Text=")"/>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
.cs
namespace SilverlightApplication2
{
public class Category
{
public int ID { get; set; }
public string Name { get; set; }
public int Count { get; set; }
}
}